US President Donald Trump lashed out Monday at the trade relationship with Japan, saying that the close ally had been “winning” for decades at the expense of the United States.

Speaking to Japanese and US business leaders on the second day of his Asia tour, Trump complained that the trade relationship between the pair was “not fair and open.”

“I have to say for the last many decades Japan has been winning,” he said.

“Many millions of cars are sold by Japan into the United States whereas virtually no cars go from the United States into Japan.”

“The US has suffered massive trade deficits with Japan for many, many years, almost $70 billion annually. So we will have to negotiate and we will do this in a friendly way.”

Trump has formed a strong bond with Prime Minister Shinzo Abe and the pair already discussed trade in an informal setting on the golf course on Sunday.

His nearly two-week Asian tour is set to be dominated by the North Korea nuclear and missile crisis but US officials have also made it clear that trade is high on their agenda.

The White House has sought to emphasise the length of the five-nation tour – the longest by any US president since George H.W. Bush in 1991 – as evidence of Trump’s commitment to engaging with the region.

But doubts linger, most notably on the economic front following Trump’s abrupt decision – three days into office – to pull out of the TPP Trans-Pacific trade deal, unsettling several signatories and Japan in particular.

Nevertheless, Trump again stressed his close bond with Abe, saying he “cherished” his friendship with the Japanese leader, whom he called a “terrific person”

“The prime minister is ordering a lot of military equipment, as he should be with what’s happening,” said Trump in an allusion to North Korea, which has threatened to “sink” Japan into the sea.